feat(smart-app): implement complete mobile app MVP

- App.tsx: full navigation (Auth stack + Main tabs with 5 screens)
- Auth: LoginScreen, RegisterScreen, ForgotPasswordScreen
- HomeScreen: dashboard with IoT metrics, weather widget, alerts, quick actions, sensors
- MapScreen: interactive map with layer toggles (6 layers)
- MarketplaceScreen: categories (6), products (5), search
- ChatScreen: AI chat with quick prompts (4), bot responses
- ProfileScreen: user info, stats, menu (9 items), logout
- AlertsScreen: alert list with severity, acknowledge
- SensorsScreen: sensor list with type filters (6 types), search
- ZonesScreen: zone cards with stats
- SettingsScreen: language picker (FR/EN/ES/DE), privacy, about
- Stores: iotStore (sensors, zones, alerts), notificationStore, uiStore + i18n
- Hooks: useSensors, useAlerts, useNotifications, useLocation
- Components: Card, Button, LoadingSpinner, ErrorBoundary, Header
- Services: iotService, notificationService (with axios API client)
- Utils: formatters (temp, AQI, noise, dates), validators (email, password, IBAN)
- Theme: colors.ts with full design system (Blue Ocean palette)
- Ditto: fixed MongoDB connection, new JWT secrets, official gateway image

smart-app-city/frontend/node_modules/react-native-reanimated/Common/cpp/Tools/ThreadSafeQueue.h

@@ -0,0 +1,49 @@
+#pragma once
+
+#include <condition_variable>
+#include <mutex>
+#include <queue>
+#include <utility>
+
+namespace reanimated {
+
+//
+// Copyright (c) 2013 Juan Palacios juan.palacios.puyana@gmail.com
+// Subject to the BSD 2-Clause License
+// - see < https://opensource.org/license/bsd-2-clause/ >
+//
+template <typename T>
+class ThreadSafeQueue {
+ public:
+  T pop() {
+    std::unique_lock<std::mutex> mlock(mutex_);
+    while (queue_.empty()) {
+      cond_.wait(mlock);
+    }
+    const auto item = queue_.front();
+    queue_.pop();
+    return item;
+  }
+
+  void push(T &&item) {
+    std::unique_lock<std::mutex> mlock(mutex_);
+    queue_.push(std::move(item));
+    mlock.unlock();
+    cond_.notify_one();
+  }
+
+  bool empty() const {
+    std::unique_lock<std::mutex> mlock(mutex_);
+    const auto res = queue_.empty();
+    mlock.unlock();
+    cond_.notify_one();
+    return res;
+  }
+
+ private:
+  std::queue<T> queue_;
+  mutable std::mutex mutex_;
+  mutable std::condition_variable cond_;
+};
+
+} // namespace reanimated